Jon Niese threw 4 1/3 scoreless innings, allowed three hits, while walking one batter and striking out three, with 57 pitches in a minor-league game on Thursday.
He threw 45 pitches in a bullpen session earlier this week, one week after getting a cortisone shot in his left elbow.
Niese said he is scheduled to throw in a minor-league game on April 1, start the season on the disabled list and make his first regular season start on April 6.
He hyperextended his elbow during a game in mid-March, as well as had an MRI on his shoulder earlier this spring. He missed several starts last season as a result of a torn rotator cuff.